Card index

ABSTRACT

A card index comprising a case with a stack of index cards covered by a pivotably mounted cover member. A set of selector keys are adapted to swing the cover and with it one or several cards upwardly into a substantially vertical viewing position. Each selector key is slidably movable along an upper case surface and is coupled by a link mechanism to an associated rocking lever. The rocking levers are adapted to swing the cover member and with it a selected number of index cards having suitable recesses upwardly into the viewing position. A similarly arranged locking key serves to return the cover member and the index cards into the closed rest position of the card index.

United States Patent Kramer Apr. 16, 1974 [54] CARD INDEX FOREIGNPATENTS R APPLICATIONS lnvemorr Wolfgang Wilhelm Bernhard 1,154,4379/l963 Germany 40/l04.0l Kramer, Essen Germany 678,855 9/1966 Belgium40/lO4.0l [73] Assignee: Kommanditgesellschaft Arlac-Werk Heiko [ppenGermany Primary Examiner-Harland S. Skogqu1st Assistant Examiner-J. H.Wolfe [22] Fled: 1972 Attorney, Agent, or FirmToren & McGeady [21] Appl.No.: 247,520

[57] ABSTRACT [30] Fm'eign Application Priority Data A card indexcomprising a case with a stack of index Apr. 1, 1972 Germany 2216016cards covered by a pivotably mounted cover member. A set of selectorkeys are adapted to swing the cover [52] U.S. Cl. 40/104,01 and with itone or several cards upwardly into a sub- [51] Int. Cl- 11/00 stantiallyvertical viewing position. Each selector key [58] Fi d 0! efl 'eh 104 7is slidably movable along an upper case surface and is coupled by a linkmechanism to an associated rocking I lever. The rocking levers areadapted to swing the [56] References Cited cover member and with it aselected number of index UNITED STATES PATENTS cards having suitablerecesses upwardly into the view- 2 524 704 /1950 Henderson /10401 ingPosition A Similarly arranged bcking key serves 2:536:544 l/l95lGordenier et 8].... 40/10401 to return the Cover member and the indexcards into 2,957,260 10/1960 Zandelin 40 10401 the Closed rest positionof the Card index- 2,968,110 l/l96l Quarnstrom 40/7805 3,073.049 l/l963Levesque 40/l04.01 3 Clams 7 Dl'awmg Flgures 43%,? LY 1 16 026 260161166 1 66291 mug/111162091796 206 I 1' i T 16 i 2 I 1 11 f 3- a; E t 4'1i5 I DT 1621b I l I M0 0 201 702 20 201 20 706 I 1 10 -I i e)- erg/ 600J no, 1116 11261731 011.1151, 192 1: 414i: 4W) fii'llb 41 e e all 150151 467 45 eei if i wwt i 466 43:1 4 58 4 9 l0- i f i H2 2 61 14 11 3312 so 83 P! Is 7: 0 .\\\1\ .\l IT\11\ 12\ ws .w\15\1t\ '1-1\11PM I 54.5'1 53 5Q (10 G1 (:12 (63 PATENTEDAPR 16 e974 SHEET 1 BF 5 CARD INDEXThis invention relates to a card index comprising a case having abox-shaped bottom member and an upper case cover plate includingatray-shaped recess for receiving a plurality of indicia-bearing looselystacked sheets or cards, and a cover rotatably mounted on a horizontalaxis and adapted to cover the trayshaped recess containing the cards,the cover operatively coupled, by means of actuating members and liftingarms engaging under the stack of cards, to a number of selector keys sothat upon actuation of one of the selector keys a selected card of thestack of cards together with all cards of the stack of cards overlyingthe selected card and the cover may be moved into an approximatelyvertical position and that by actuation of a locking key the cover maybe returned into its closing position covering the tray-shaped recess,whereby the ends of the stack of cards are held, in the vicinity of thecover pivot axis, by lateral guide means and are provided at theirlongitudinal edges facing the cover pivot axis with selector recessesfor the passage of the lifting arms.

It is an object of the present invention to provide an improved cardindex of the above type which may be more economically manufactured andmore easily as-v sembled and is of an increased efficiency. Forachieving this object there is now proposed a card index of the typedescribed above which is arranged, in accordance with the presentinvention such that each selector key consists of a sliding key adaptedto be, moved transversely of the cover pivot axis and includes a tonguemovable along the surface of the upper case cover plate, a grippingactuator portion molded to its upper surface, and a neck portion moldedto its lower surface; each tongue is engaged with an associated slideslidably guided below the upper case cover plate between a pair oflateral guide wall portions molded integrally with the case bottommember; each slide connected to the tongue of an associated key by meansof the neck portion and arranged in the vicinity of a slot-shapedopening of the case upper cover plate forwardly of the trayshaped recessfor the stack of cards; the slot-shaped opening being of a lengthapproximately corresponding to the sum of the widths of all of theselector keys and being of a width exceeding the length of the neckportion engaging the slide the slide engaging a return,

spring abutting at its one end a vertical abutment molded to the frontof the pair of lateral guide wall portions in the path of movement ofthe slide, and abutting at its other free end against the slide, theslide having at its end facing the cover pivot axis an arm to which isconnected one end of an actuator rod for moving the respective liftingarm of a twoarmed rocking lever, the other end of the actuator rod beingconnected to the other arm of the rocking lever; the rocking lever beingrotatably mounted on the cover pivot axis, the width of the rockinglever arm adapted to engage one of the cards or a stack of cardsrespectively being related to the width of the tongue-shaped keys; thecard edges facing the cover pivot axis provided with the selectorrecesses whereby the recesses in the cards are progressively wider fromthe second card to the lowermost card of the stack, the width of therecesses increasing from card to card by twice the width of a rockinglever arm engaging a card or a stack of cards.

The locking key for the cover is arranged similarly to the selector keysand isconnected through an actuator rod with one arm of a two-armedrocking lever adapted to be rotated on a vertical axis on the floor ofthe case bottom member whereas the other free rocking lever arm isconnected with the cover pivot axis in such a manner that upon actuationof the locking key the cover may be moved into its closing position.

An illustrative exemplary embodiment of the present invention is shownin the appended drawing wherein FIG. 1 is a top view of a card indexaccording to the present invention;

FIG. 2 is a top view of the card index of FIG. 1

wherein the cover is swung upwardly into an opened position;

FIG. 3 is a top view of the card index after removal of the upper casecover plate;

FIG. 4 is a lateral cross-sectional view corresponding cover plate 12adapted to closethe bottom member and provided with a desk-like inclinedfront portion 12a. The upper case cover plate 12 is provided with atray-shaped recess 13 for receiving a stack of cards 100. This stack ofcards may consist of a number of sheets or cards bearing indicia or thelike. In the here described and illustrated embodiment there areprovided thirteen index cards which are referenced 101, 102, 103, 104,105, 106, 107, 108, I09, 110, 111, 112 and 113 respectively, as may beseen in FIGS. 5, 6 and 7. The individual cards are provided on theirfront and rear surfaces with line patterns serving to facilitate theentering of names, addresses and phone numbers or the like. The cardsare also imprinted with the letters of the alphabet in such a mannerthat the card 101 bears on its surface facing the next following card102 the letter A whereas each of the following cards 103 113 isimprinted with two letters each, the one of which is imprinted on thefront surface and the other of which is imprinted on the rear surface ofthe card. The cards 102 to 113 are furthermore provided at theirlongitudinal edges facing the rear of the case 10 with selector recesses114, 115, 116, 117, 118, 119, I20, 121, 122, 123, 124 and 125respectively the purpose of which will be explained further below. Thenarrow card sides along the longitudinal card edges are provided,approximately in the same height as the selector recesses 114 to 125,with further slot-shaped recesses 126, 127 serving to hold and guide thecards in the card index case 10 (FIG. 6).

The tray-shaped recess 13 may be closed by means of a cover 15 which ispreferably of a box-shaped configuration and includes a peripheral edgeof a height corresponding to the one of the stack of cards 100 (FIG. 4).The cover 15 is rotatably mounted in the direction of the arrow x bymeans of a pivot axis -l6 mounted on the case bottom member. 11. Thecover .15 is laterally provided on either side with an arcuate guiderail l7, 18 consisting of angle profiles that are each guided by one oftheir two flanges in the recesses 126, 127 of the index cards 101 to113. In this manner, the index cards 101 to 113 are held on the cover 15also when the cover and with it the cards are swung upwardly (FIG. 2).

The selector keys 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 and alocking key 32 are provided on the desk-like inclined front portion 12aof the upper case cover plate 12 forwardly of the tray-shaped recess 13.The selector keys 20 to 31 serve to move any selected card into theviewing" position (FIGS. 2, 4 and 5) whereas by means of the key 32 theswung up cover will be returned into its closing position. Everyselector key to 31 as well as the locking key 32 is provided on itsupper surface with a wedge-shapedactuator portion 33 as may be seen bestin FIG. 4. The mutual arrang'ement of these actuator portions 33 in suchthat the actuator portions 33 on the individual selector keys 20 to 31and the locking key 32 are mutually staggered so that the readyactuation of the individual selector keys are aasured (FIG. 2). Theselector keys 20- 31 and the locking key 32' are arranged in the form ofsliding keys that are slidable transversely of the cover pivot axis 16.Each selector key consists of a tongue 35 slidable along the uppersurface of the upper case cover plate 12,'and a neck portion 36connected to a slide 40 that is movably'guided in the interior of thecase below the upper cover plate 12. The neck portion 36 of eachselector keyis disposed within a slot-shaped opening 38 in the uppercase cover plate 12. The length of this slotshaped opening 38 is equalto the sum of-the widths of all selector keys 20 to 31 and the lockingkey 32. The width of the slot-shaped opening 38 is somewhat larger thanthe length of the neck portion 36 on each selector key so that the neckportion 36 may be shifted within the slot shaped opening 38 transversely to the longitudinal extension thereof. Since the tongue and the slideof each selector key .are longer than the width of the slot-shapedopening 38, each selector key is properly guided on the upper case coverplate 12.

The slides that are'associated to the various selector keys 20 to 31 andthe locking key 32 and are guided in the interior of the case arereferenced 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 and 52respectively (FIG.

3). Each slide 40 to 52 is guided on a guide plate 53 exvided'at thefront end of the guide pathof each slide 40 to 52 between thecorresponding pair of guide wall portions. A spring such as the oneindicated by the reference 83 bears at its one end against one of theselug earns 70 to 82 and bearswith its other free end against anotherlugcam 84 provided in the interior of the slide having a channel shapedcross-section. Aispring 83 is disposed within the interior of each slide40 to 52. The slides 40 to 52 are each provided at their ends facingthe'cover pivot axis 16 with an approximately vertically extendingarm130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141 and 142respectively. At its bottom end, each arm is provided with an opening143 through which the free offset end of an actuator rod extends. Theactuator rods for the various slides are referenced 150, "151, 152, 153,154, 155,- 156, 157, 158, 159, 160,

161 and 162 respectively (FIGS.'3 and 4). The other 176a, 177a, 178a,179a, 180a, 181a of a two-armed rocking lever 170, 171, 172, 173, 174,.175, 176, 177, 178, 179, 180 and 181 respectively the number of whichcorresponds to the number of selector keys 20 31. The other arms ofthese rocking levers to .181 are referenced 170b, 171b, 172b, 173b,174b, 175b, 176b, 177b, 1781;, 179b, 1801: and 1811; respectively. Therocking levers 170 to 181 are each of a width corresponding to the widthof one of the selector keys 20 to 31 and are rotatably mounted on thecover pivot axis 16, as may be seen in FIGS. 3 and 4. The arms 17% to18111 of the rocking levers 170 to serve as lifting arms and engage,upon actuation of the associated selector key, the cards in the stack ofcards 100which are associated to the respective arms 17% to 18112. Theoverall arrangement is such that for example when the selector key 20 isactuated in the direction of the arrow y (FIG. 1) the selector key 20thus taking the position shown in FIGS. 2 and 3 the arm 1701; of therocking lever 170 engages the card 101. By actuation of this selectorkey the arm 17% is rotated in the direction of the arrow y, (FIG. 4) andmoves simultaneously the cover 15 from its closing position into thesubstantially vertical position shown in FIG. 4 whereby the card 101will be moved into the same position as the cover 15. When for examplethe selector key 24 will be actuated, the actuator rod 154 rotates therocking lever 174 in such a manner that the rocking lever arm 1741;engages the card 105 and thus moves this card 105 together with, theoverlying cards 101, 102, 103,104, and the'cover 15 into the openedposition of the card index.

The swung up cover 15 may be returned into the closing position by meansof the locking key 32. The

of the rocking lever is connected by means of an actuator rod 192 to thecover pivot axis 16 in'such a mannerthat upon actuation of the lockingkey 32 in the direction of the arrow y (FIG. 3) the pivot axis 16 willbe rotated in a direction in which the cover 15 is moved together withthe cards on the cover into the closing position. Simultaneously theactuated selector key is returned into its initial position by means ofthe return spring 83 (FIG. 3). I

- The cover 15 may also be returned into the closing position by meansof an engagement of the rocking lever 190 with the offset cover portion150 (FIG. 4). The inventive card index is used as follows: Theindividual indicia-bearing cards of the stack of cards 100 areassociated to the individual selector keys 20 to 31 which are likewiseprovided with'corres'ponding indicia or corresponding reference or codenumbers (FIG. 2). When for example the selector key 20 is movedv in thedirection of the arrow y (FIG. 1) along the upper case cover plate 12the associated actuator rod 150 will be moved in the same direction androtates thereby the associated rocking lever, in the present instancethe rocking lever 170, in such a manner that the rocking lever arm170b'will swing the card 101 upwardly, together with the cover 15. Thusthe card will be moved together with the cover serving as a support intoa viewing position in which the selected card is freely visible. Whenactuating the selector key 20, the spring 83 within the slide 40 will becompressed. When actuating the locking key 32 the cover 15 together withthe card or the cards lying in the cover will be returned into theclosing position whereby simultaneously the key will be returned intoits initial position by means of the return spring 83. In order that thelifting arms 170b to 181b take a substantially horizontal position whenthe card index is in its rest position the arms 1701; to 181b rest onvertical cams 200, 201, 203, 204, 205, 206, 207, 208, 209, 210 and 211respectively that are molded integrally with the floor of the casebottom member 11. Due to these cams 200 to 211 a relatively small swivelmovement is required for moving the cover 15 into its opened position.On the other hand, the travel of the selector keys 20 to 31 may be keptrelatively short.

All parts of the card index, apart from the cover pivot axis 16, theactuator rods 150 to 162 and the return springs 83 are preferably madeof plastic materials or any other suitable materials.

The inventive card index may be made of a relatively small number ofmutually identical constructional elements which are readily combinedand assembled. This allows for a more economical assembly of the cardindex. By the fact that the selector keys consist of sliding keys asdescribed a perfect operation of the card index is assured. By thefeatures of using key slides and slide tracks any tilting of theselector keys is avoided and moreover no scratch marks will appear onthe case outer surface in the region of the selector keys even afterextended periods of usage of the card index.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In a card index comprising a case having a horizontally arrangedbox-shaped bottom member and an upper case cover plate spaced above saidbox-shaped bottom member and forming a space therebetween, said coverplate having a tray-shaped recess in its upper surface, a plurality ofelongate rectangular horizontally arranged indicia-bearing cards stackedone above the other in said tray-shaped recess, means including ahorizontally arranged pivot axis mounted in said boxshaped bottommember, a cover rotatably mounted on said horizontal pivot axis so thatit is positionable between a closed position covering the tray-shapedrecess and an opened position extending upwardly from said box-shapedmember affording visual access to the contents of the recess, furthermeans located within said bottom member and operatively coupled to saidcover for rotating said cover between the closed and opened positions, anumber of selector keys elongated in the direction transverse to thehorizontal pivot axis of said cover and mounted on said cover plate andhaving means so that upon the actuation of one of said selector keys aselected one of said cards together with all said cards of the stackoverlying the selected one of said cards and said cover can be movedinto the opened position in an approximatley vertical position, alocking key associated with said means operatively coupled to said coverfor returning said cover into its closed position covering, thetray-shaped recess, lateral guides located adjacent of said pivot axisfor holding the stack of said cards in a stacked arrangement, said cardshaving longitudinal edges adjacent said pivot axis and containingselector recesses for the selective passage of said means operativelycoupled to said cover, each said selector key arranged to move in thehorizontal direction transversely of the horizontal pivot axis of saidcover, a separate double-arm rocking lever associated with each saidselector key, said means operatively coupled to said cover beingconnected to said rocking levers, and a separate spring associated witheach said selector key, wherein the improvement comprises that saidcover plate in the portion thereof opposite from the horizontal pivotaxis comprise a recess therein having a slot-shaped opening which has alength extending parallel to the horizontal pivot axis of said cover andits length corresponds approximately to the sum of the widths of all ofsaid selector keys extending in the same direction and having a widthless than the length of said selector keys, each said selector keyhaving means which include a tongue slidable over the upper surface ofsaid cover plate and bridging said slot-shaped opening, a grippingactuator portion molded on and extending upwardly from the upper surfaceof each said tongue, a neck portion secured to the underside of eachsaid tongue and extending downwardly therefrom through said slot-shapedopening into the space formed by said box-shaped bottom member and uppercase cover plate, said neck portion extending in the width direction ofsaid slot shaped opening a slide secured to said neck portion andlocated in the space formed by said bottom member and cover plate, aplurality of laterally spaced parallel guide wall portions extendingtransversely of the horizontal pivot axis of said cover and formedintegrally with said bottom member, each pair of adjacent said guidewall portions forming a guide for one of said slides, a first lug camlocated between and extending transversely of each pair of adjacent saidguide wall portions, a second lug cam secured to and extendingdownwardly from each said slide, said second lug cam locatedintermediate said first lug cam and the horizontal pivot axis of saidcover plate, each said spring for said selector keys extending betweensaid first and second lug cams associated with the respective saidselector key, the end of each said slide facing the horizontal pivotaxis of said cover plate having a downwardly extending arm with anopening therethrough, said means operatively coupled to said coverincluding a separate actuator rod for each said selector key, each saidactuator rod coupled to the opening in the associated one of said slidesand extending therefrom toward the horizontal pivot axis of said coverplate, each said rocking lever mounted on the horizontal pivot axis ofsaid cover plate having a first arm to which the corresponding end ofsaid actuator rod remote from said cooperating slide is connected and asecond arm which is arranged to engage under a an appropriate one ofsaid cards to lift it and any overlying said cards, said second armhaving a width which substantially corresponds to the width of saidtongueshaped keys, the selector recesses in the edges of said cardsfacing the horizontal pivot axis of said cover are arranged so that saidselector recesses are progressively wider from the second card from thetop of the stack to the lowermost card of the stack, and the width ofsaid recesses increasing from card to card by twice, the

width of one of said second arm of said rocking levers, and said coveris spaced above the recess in said cover plate so that a space is formedabove the stack of said cards which is approximately twice as high asthe stack of said cards.

2. A card index according to claim 1, wherein said locking key for saidcover comprises a wide tongue slidable over the surface of said'coverbridging said slotshaped opening, a gripping actuator portion molded onand extending upwardly from the upper surface of said tongue, a neckportion secured to the under side of said tongue and extendingdownwardly therefrom through said slot-shaped opening into the spaceformed by said bottom member and cover plate, said neck portionextending in the width direction of said slot-shaped opening and havinga length which is a fraction of the width of said slot-shaped opening, aslide secured to said neck portion and located in the spaced formed bysaid bottom member and cover plate, the end of said slide located closerto the pivot axis of said cover plate having a downwardly extending armwith an opening therethrough, said means operatively coupled to saidcover including an actuator rod connected at one end to the opening insaid slide, a vertical pivot axis secured to the floor of said bottommember, a two-armed rocking lever.'mounted on said vertical pivot axisand the end of said actuator rod remote from said slide being connectedto one of the arms of said rocking lever, the other said arm of saidrocking lever beingconnected-to the horizontal pivot axis of said coverso that as said moved from its opened into its closed position.

3. A card index according to claim 1, wherein said locking key for saidcover comprises a wide tongue slidable over the surface of said cover, agripping actuator portion molded on and extending upwardly from theupper surface of said tongue, a neck portion secured to the under sideof said tongue and extending downwardly therefrom through saidslot-shaped opening into the space formed by said bottom member andcover plate, said neck portion extending in the width direction of saidslot-shaped opening and having a length which is a fraction of the widthof said slot-shaped opening, a slide secured to said neck portion andlocated in the space formed by said bottom member and cover plate, theend of' said slide located closer to the pivot axis of said cover platehaving a downwardly extending arm with an opening therethrough, saidmeans operatively coupled to said cover including an actuator rodconnected at one end to the opening in said slide, a vertical pivot axissecured to the floor of said bottom member, a two-armed rocking levermounted on said vertical pivot axis and the end of said actuator rodremote from said slide being connected to one of the arms of saidrocking lever, said cover having an offset cover portion, the other saidarm of said rocking lever being arranged to engage said offset coverportion of said cover for returning said cover from its open to itsclosed position.

" i v i

1. In a card index comprising a case having a horizontally arrangedbox-shaped bottom member and an upper case cover plate spaced above saidbox-shaped bottom member and forming a space therebetween, said coverplate having a tray-shaped recess in its upper surface, a plurality ofelongate rectangular horizontally arranged indicia-bearing cards stackedone above the other in said tray-shaped recess, means including ahorizontally arranged pivot axis mounted in said box-shaped bottommember, a cover rotatably mounted on said horizontal pivot axis so thatit is positionable between a closed position covering the tray-shapedrecess and an opened position extending upwardly from said boxshapedmember affording visual access to the contents of the recess, furthermeans located within said bottom member and operatively coupled to saidcover for rotating said cover between the closed and opened positions, anumber of selector keys elongated in the direction transverse to thehorizontal pivot axis of said cover and mounted on said cover plate andhaving means so that upon the actuation of one of said selector keys aselected one of said cards together with all said cards of the stackoverlying the selected one of said cards and said cover can be movedinto the opened position in an approximatley vertical position, alocking key associated with said means operatively coupled to said coverfor returning said cover into its closed position covering, thetray-shaped recess, lateral guides located adjacent of said pivot axisfor holding the stack of said cards in a stacked arrangement, said cardshaving longitudinal edges adjacent said pivot axis and containingselector recesses for the selective passage of said means operativelycoupled to said cover, each said selector key arranged to move in thehorizontal direction transversely of the horizontal pivot axis of saidcover, a separate double-arm rocking lever associated with each saidselector key, said means operatively coupled to said cover beingconnected to said rocking levers, and a separate spring associated witheach said selector key, wherein the improvement comprises that saidcover plate in the portion thereof opposite from the horizontal pivotaxis comprise a recess therein having a slot-shaped opening which has alength extending parallEl to the horizontal pivot axis of said cover andits length corresponds approximately to the sum of the widths of all ofsaid selector keys extending in the same direction and having a widthless than the length of said selector keys, each said selector keyhaving means which include a tongue slidable over the upper surface ofsaid cover plate and bridging said slot-shaped opening, a grippingactuator portion molded on and extending upwardly from the upper surfaceof each said tongue, a neck portion secured to the underside of eachsaid tongue and extending downwardly therefrom through said slot-shapedopening into the space formed by said box-shaped bottom member and uppercase cover plate, said neck portion extending in the width direction ofsaid slot shaped opening a slide secured to said neck portion andlocated in the space formed by said bottom member and cover plate, aplurality of laterally spaced parallel guide wall portions extendingtransversely of the horizontal pivot axis of said cover and formedintegrally with said bottom member, each pair of adjacent said guidewall portions forming a guide for one of said slides, a first lug camlocated between and extending transversely of each pair of adjacent saidguide wall portions, a second lug cam secured to and extendingdownwardly from each said slide, said second lug cam locatedintermediate said first lug cam and the horizontal pivot axis of saidcover plate, each said spring for said selector keys extending betweensaid first and second lug cams associated with the respective saidselector key, the end of each said slide facing the horizontal pivotaxis of said cover plate having a downwardly extending arm with anopening therethrough, said means operatively coupled to said coverincluding a separate actuator rod for each said selector key, each saidactuator rod coupled to the opening in the associated one of said slidesand extending therefrom toward the horizontal pivot axis of said coverplate, each said rocking lever mounted on the horizontal pivot axis ofsaid cover plate having a first arm to which the corresponding end ofsaid actuator rod remote from said cooperating slide is connected and asecond arm which is arranged to engage under a an appropriate one ofsaid cards to lift it and any overlying said cards, said second armhaving a width which substantially corresponds to the width of saidtongue-shaped keys, the selector recesses in the edges of said cardsfacing the horizontal pivot axis of said cover are arranged so that saidselector recesses are progressively wider from the second card from thetop of the stack to the lowermost card of the stack, and the width ofsaid recesses increasing from card to card by twice, the width of one ofsaid second arm of said rocking levers, and said cover is spaced abovethe recess in said cover plate so that a space is formed above the stackof said cards which is approximately twice as high as the stack of saidcards.
 2. A card index according to claim 1, wherein said locking keyfor said cover comprises a wide tongue slidable over the surface of saidcover bridging said slot-shaped opening, a gripping actuator portionmolded on and extending upwardly from the upper surface of said tongue,a neck portion secured to the under side of said tongue and extendingdownwardly therefrom through said slot-shaped opening into the spaceformed by said bottom member and cover plate, said neck portionextending in the width direction of said slot-shaped opening and havinga length which is a fraction of the width of said slot-shaped opening, aslide secured to said neck portion and located in the spaced formed bysaid bottom member and cover plate, the end of said slide located closerto the pivot axis of said cover plate having a downwardly extending armwith an opening therethrough, said means operatively coupled to saidcover including an actuator rod connected at one end to the opening insaid slide, a vertical pivot axis secured to the floor of said bottommember, a two-armed rocking lever mounted on said vertical pivot axisand the end of said actuator rod remote from said slide being connectedto one of the arms of said rocking lever, the other said arm of saidrocking lever being connected to the horizontal pivot axis of said coverso that as said locking key is actuated said cover member can be movedfrom its opened into its closed position.
 3. A card index according toclaim 1, wherein said locking key for said cover comprises a wide tongueslidable over the surface of said cover, a gripping actuator portionmolded on and extending upwardly from the upper surface of said tongue,a neck portion secured to the under side of said tongue and extendingdownwardly therefrom through said slot-shaped opening into the spaceformed by said bottom member and cover plate, said neck portionextending in the width direction of said slot-shaped opening and havinga length which is a fraction of the width of said slot-shaped opening, aslide secured to said neck portion and located in the space formed bysaid bottom member and cover plate, the end of said slide located closerto the pivot axis of said cover plate having a downwardly extending armwith an opening therethrough, said means operatively coupled to saidcover including an actuator rod connected at one end to the opening insaid slide, a vertical pivot axis secured to the floor of said bottommember, a two-armed rocking lever mounted on said vertical pivot axisand the end of said actuator rod remote from said slide being connectedto one of the arms of said rocking lever, said cover having an offsetcover portion, the other said arm of said rocking lever being arrangedto engage said offset cover portion of said cover for returning saidcover from its open to its closed position.